Inline real-time process monitoring based on ultrasonic measurement and tomography
Type:
Presented during:
CEDA Dredging Days 2024
Authors:
R. Maas and M. Boerma
Abstract
Slurry density measurement is a vital part of many industrial processes. Over the past decades, industries such as dredging, mining and mineral processing predominantly relied on nuclear density meters (also known as radiometers). However, because of stricter government regulations, rising safety-related costs and the need to reduce nuclear waste, industries - in particular dredging companies - are increasingly looking for non-nuclear measuring instruments. Rhosonics has introduced an alternative to radiometers, by developing an ultrasound-based densitometer called the Slurry Density Meter (SDM). The SDM applies an advanced technology based on the reflection across the interface to measure the density of the slurry in a cross-section of the pipe. Measuring the bulk density of the slurry for a non-homogeneous flow presents an extra challenge. To address this, a special modular pipe integration has been developed called the ultrasonic pocket. The pocket consists of two sensors placed opposite each other and perpendicular to the flow in the pipe. In the pocket the bulk density and solid concentration can be measured continuously. Moreover, the modular design allows multiple sensors to be placed around the pipe. Additionally, an algorithm has been developed based on tomography and combining the measurement of the pockets together. This enables real-time measurement of the bulk density and solids distribution in the cross-section of the pipe. This innovative technology can reveal layers inside the pipe and detect sand accumulation, preventing the pipe from clogging up and blocking the pump, which consequently reduces maintenance time and cost. In short, with the real-time inline measurement of the cross-section of the pipe, the operational process can be optimized and the pump can be controlled for optimal power. The primary advantages of this include a reduction in fuel consumption and carbon dioxide emissions. This paper describes the outcome of the study conducted in collaboration with TU Delft, including a validation test in the laboratory, and the further development of the pocket for inline integration.
Keywords: Ultrasonic density measurement, Viscous Sublayer Effects, Sensor Technology, Pocket Design, Density Control Challenges